Increasing oil prices and national legislation requiring the reduction of automotive carbon dioxide emissions force tire and rubber producers to produce “fuel-efficient” and thus fuel-saving tires. One approach for obtaining fuel-efficient tires lies in the production of tire formulations having reduced hysteresis loss. The hysteresis loss of a cross-linked elastomeric polymer composition is related to its tan δ value at 60° C. (see ISO 4664-1:2005; Rubber, Vulcanized or thermoplastic; Determination of dynamic properties—part 1: General guidance). In general, vulcanized elastomeric polymer compositions having relatively low tan δ values at 60° C. are preferred as having lower hysteresis loss. In the final tire product, this translates into a lower rolling resistance and better fuel economy. In contrast, a lower tan δ value at 0° C. corresponds to a deteriorated wet grip of the tire product. Thus, it is generally accepted that a lower rolling resistance tire can be made at the expense of deteriorated wet grip properties. For example, if, in a random solution styrene-butadiene rubber (random SSBR), the polystyrene unit concentration is reduced with respect to the total polybutadiene unit concentration, the SSBR glass transition temperature is reduced and, as a result, both tan δ at 60° C. and tan δ at 0° C. are reduced, generally corresponding to improved rolling resistance and deteriorated wet grip performance of the tire. Accordingly, when assessing the rubber vulcanizate performance correctly, both tan δ at 60° C. and tan δ at 0° C. should be monitored along with the tire heat build-up.
WO 2012/091753 relates to silane-functionalized polymers and rubber vulcanizates prepared therefrom. The authors describe the use of certain alkenylaminosilanes for use in the initiation of anionic polymerizations.
US 2010/0056712 relates to a conjugated diene polymer obtained by polymerizing a conjugated diene monomer and a vinylaminosilane in the presence of an alkali metal catalyst.
WO 2011/028523 relates to a process for preparing a polydiene, the process comprising the polymerization of a conjugated diene monomer with a lanthanide-based catalyst system in the presence of a vinylsilane, an allylsilane, or an allylvinylsilane.
The present invention aims the provision of cured elastomeric polymer (rubber) compositions exhibiting reduced heat build-up and improved tan δ values, corresponding to an improved balance of rolling resistance and wet grip performance.